In the construction of cased electrical components, such as multiple electrical outlet strips, it is desirable to provide as simple a construction, utilizing the simplest manufacturing techniques, as possible, while not sacrificing safety or quality. Advances have been made in the art to this end, as exemplified by the structures in U.S. Pat. Nos. 4,072,401 and 4,113,334, wherein multiple electrical outlet strips are provided that are relatively simple and inexpensive to construct yet provide all desired functions. According to the present invention the construction of cased electrical components, such as multiple electrical outlet strips, is provided which achieves even greater simplicity and cost reductions than are achieved with the structures and procedures disclosed in the above-identified patents.
In prior art constructions of multiple electrical outlet strips utilizing metal casings, grounding of the electrical component or components to the metal casing has been effected in a relatively complicated manner. Normally a stud or flange is formed, and is soldered or welded to the metal casing, and a ground wire is then led from the electrical component or components to the stud or flange. According to the present invention the separate operations associated with forming or welding or soldering the stud or flange are eliminated. A grounding tab is formed integrally with the casing during the operation of punching the opening through which the electrical cord will extend into the casing. The tab is bent over when the electrical cord is inserted into the casing, and the ground wire may be soldered directly to the tab. This results in reduced material costs as well as substantial ease of manufacture.
Conventionally the cover and base components of multiple electrical outlet strip casing are connected together by bending over cooperating tab portions on extending ears, or by pop riveting the components together when the cover and/or the base do not have an ear. According to the persent invention the cover and base are connected together in a manner much simpler than either of these two prior art arrangements, and with reduced material costs, neither a pair of ears nor pop rivets being necessary. Attachment of the casing pieces together according to the present invention is accomplished by forming snap-connection means integrally with both the cover and base. For instance, a plurality of openings are provided in opposite side edges upstanding from the base, and integral projections are formed in opposed cover side walls by deforming portions thereof. The projections and openings readily snapped together and provide a tight interference fit. In this way ease of manufacture and assembly is facilitated, disassembly is possible, and at the same time the necessary tight interengagement between the cover and base is maintained.
According to the present invention temporary mounting openings are provided for the cased electrical component in an advantageous way compared to the prior art. Typically in the prior art accessory metal "hats" with shelf portions having temporary mounting openings formed therein are welded or otherwise affixed to the base of the casing. According to the present invention the necessity for such accessory components is eliminated by forming the temporary mounting openings (typically having a cruciform construction) directly in the casing base. In order to prevent penetration of mounting screws, or other mounting components, through the temporary mounting openings into contact with the electrical components mounted within the casing, a stiff piece of electrical insulating material, such as LEXAN, is provided between the base and the electrical components. The LEXAN sheet may merely be inserted into the casing during assembly, there being no necessity for affixing it to either casing piece, the sheet preferably being dimensioned so that an interference-type fit is provided between it and casing cover.
A cased electrical component according to the present invention has greatly simplified construction, and is substantially less expensive, than prior art cased electrical components having the same functionality. It is the primary object of the present invention to provide for the simplified construction of a cased electrical component while not sacrificing functionality. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.